IN VITRO STUDY OF THE ANTIOXIDANT POTENTIAL OF SOME TRADITIONALLY USED MEDICINAL PLANTS OF NORTH-EAST INDIA AND ASSESSMENT OF THEIR TOTAL PHENOLIC CONTENT

Abstract

Summary The antioxidant activity of four traditionally used medicinal plants found in the North East region of India was determined. The methanol and aqueous extracts of the plants were evaluated for their in vitro scavenging effects on 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and the reactive oxygen species (ROS), hydroxyl ion (OH•), superoxide anion (O2 • ⎯) free radicals and hydrogen peroxide (H2O2). The methanol extracts exhibited varying DPPH and H2O2 scavenging activity with Osbeckia chinensis (IC50= 12.74 ± 0.35 µg/ml) showing the highest activity against DPPH and Potentilla fulgens (IC50= 40.5 ± 1.78 µg/ml) against H2O2. The aqueous extract of Potentilla fulgens was found to be the most active in scavenging O2 • ⎯ radicals (IC50= 14.68 ± 1.07 µg/ml) while the aqueous extract of Flemingia macrophylla comparatively exhibited the highest scavenging activity